// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/quic/quic_address_mismatch.h"

#include "base/logging.h"
#include "net/base/ip_address.h"

namespace net {

int GetAddressMismatch(const IPEndPoint& first_address,
    const IPEndPoint& second_address)
{
    if (first_address.address().empty() || second_address.address().empty()) {
        return -1;
    }
    IPAddress first_ip_address = first_address.address();
    if (first_ip_address.IsIPv4MappedIPv6()) {
        first_ip_address = ConvertIPv4MappedIPv6ToIPv4(first_ip_address);
    }
    IPAddress second_ip_address = second_address.address();
    if (second_ip_address.IsIPv4MappedIPv6()) {
        second_ip_address = ConvertIPv4MappedIPv6ToIPv4(second_ip_address);
    }

    int sample;
    if (first_ip_address != second_ip_address) {
        sample = QUIC_ADDRESS_MISMATCH_BASE;
    } else if (first_address.port() != second_address.port()) {
        sample = QUIC_PORT_MISMATCH_BASE;
    } else {
        sample = QUIC_ADDRESS_AND_PORT_MATCH_BASE;
    }

    // Add an offset to |sample|:
    //   V4_V4: add 0
    //   V6_V6: add 1
    //   V4_V6: add 2
    //   V6_V4: add 3
    bool first_ipv4 = first_ip_address.IsIPv4();
    if (first_ipv4 != second_ip_address.IsIPv4()) {
        CHECK_EQ(sample, QUIC_ADDRESS_MISMATCH_BASE);
        sample += 2;
    }
    if (!first_ipv4) {
        sample += 1;
    }
    return sample;
}

} // namespace net
